Grease and other impurities such as smoke, soot, and the like are emitted into the air when foods that contain oily substances are cooked. When these types of food are cooked indoors, a ventilation system is often used to channel the cooking exhaust out of the building and into the atmosphere. In an effort to prevent the buildup of grease and other impurities on the interior of ventilation system (e.g., the hood, ductwork, fan, etc.), the air may be filtered using mesh or baffle filters before or shortly after entering the ventilation system. If the grease is not filtered out of the exhaust stream, it may build up on the inside of the ventilation system. Grease build-up in the ventilation system may create a dangerous fire situation or a situation which is unsanitary for a cooking environment. Also, if the grease isn't filtered out of the air, the grease may accumulate near the exit of the ventilation system (e.g., the roof of the building).
Many kitchen ventilation systems include a hood and ductwork which extend from the hood to the exterior of the building. Baffle filters used with these hoods generally operate by deflecting the cooking exhaust flow as it passes through the baffle so that heavier substances (e.g. liquids such as grease, solids, etc.) impact the surface of the baffle. After impacting the surface of the baffle, these substances drain to a collection area. In addition to filtering grease, the baffle filters are often required by local laws or generally agreed upon standards to have a minimum level of flame retarding capability. Thus the baffle filter may be used to prevent flare-ups on the cooking surface or other fires that may occur from easily spreading into the ductwork.
Unfortunately, conventional baffle filters suffer from a number of deficiencies. For example, in many conventional baffle filters, the capture efficiency and flame retarding capability of the baffle filter are relatively low. As a result of the low capture efficiency, these filters generally capture only larger substances and allow more impurities to pass through the filters and deposit in the ductwork. The ductwork may require more frequent cleaning and maintenance as a result, which, in turn, increases the costs of operating and maintaining the facility.
Accordingly, it would be advantageous to provide an improved baffle filter which is capable of higher capture efficiencies and/or flame retarding capability than many of the presently available baffle filters. It would also be desirable to provide a baffle filter that is economical and easy to use.